Generic fabrication technology for transparent and suspended microfluidic and nanofluidic channels

A promising method for fabricating suspended and transparent microfluidic and nanofluidic channels systems made of a thermally grown silicon dioxide is presented. The fabrication is based on the growth of a thermal silicon dioxide in open cavities formed at the interface of two wafers. We demonstrate three different designs of micro- and nanofluidic channels for three applications: 1) Electroosmotic flow measurements through micro- and nanofluidic channel systems were used to estimate the electroosmotic mobility. 2) Resonance measurements on suspended and filled, 100 μm long microchannels were optically performed by using 10 × 10 μm large, integrated and aluminum coated silicon dioxide mirrors. 3) Hollow cantilevers with a FIB-milled pore at the tip apex were fabricated and used to record scanning force microscopy images.